There has been two threads lately discussing anchoring and the technical aspects of drag sensing.

You can over analyze anything. You can focus on one single aspect of anchoring (Gps inaccuracy) and get caught up in the details.

The reality is that setting your anchor and having the confidence to know you are safe depends on allot of different data sources. Position is one, but depth, proximity to other objects, etc... All combine to create a picture in your mind.